Patent Application FR2541005 discloses a mechanism for the display and adjustment of the date implemented by means of an epicyclic gear train, of which the output takes the form of a crown equipped with a calendar driving finger which is capable of being in engagement with a calendar driving disk. During the conventional operation of the timepiece, the planetary gear carrier is engaged by the kinematic chain for driving the calendar, which is in engagement with the hour wheel. In this configuration, the sun gear is fixed by means of a correction wheel which is indexed by a spring. The planetary gear thus moves relative to the pinion and drives the crown rotatably by means of the internal toothing of the latter. The planetary gear carrier is in direct engagement with the hour wheel, so that a rotation of the hour hand necessarily entails a rotation of the crown. It is thus not possible to set the time without acting on the adjustment device of which the epicyclic gear train forms part. Furthermore, a suchlike construction of an epicyclic gear train is not optimal to the extent that it requires a particularly complicated crown, which combines internal and external toothing. The tolerances of the guide portions must thus be minimized to the greatest possible extent so as to reduce the radial and longitudinal movements, and thus to minimize the risks of butting between the different toothings. The crown must likewise be sufficiently thick to combine an internal toothing and a guide portion sufficient to permit appropriate pivoting.
Patent Application EP2615506, for its part, discloses a specific design of an epicyclic gear train which is provided in order to permit the adjustment of a device for the display of the phases of the moon. The first input of the planetary gear set is constituted by a crown, of which the external toothing is in engagement with the going train of the basic movement, in particular by means of the hour wheel, and of which the internal toothing is in engagement with at least one planetary gear mounted in a pivotable manner on a planetary gear carrier in engagement with the wheel for the display of the phases of the moon. The second input of the planetary gear set is constituted by a correction star of the phases of the moon, of which the angular position is provided in order to be locked by a jumper, and of which the actuation is controlled by a correction rocker bar. This star is likewise in engagement with the planetary gear by means of a wheel which is integral therewith. During the conventional operation of the timepiece, the display wheel is actuated by the hour wheel by the intervention of the planetary gear carrier and its planetary gear, which pivots relative to the correction wheel. During the correction phase, the display wheel is actuated by the wheel by the intervention of the planetary gear carrier and its planetary gear, which pivots relative to the crown. The first input of the planetary gear set is in direct engagement with the hour wheel, so that a rotation of the element for the display of time necessarily entails a rotation of the display wheel. It is thus not possible to set the time independently of the adjustment device in which the epicyclic gear train plays a part. Furthermore, a suchlike construction of the epicyclic gear train in not optimal to the extent that it requires a crown equipped with a first internal toothing and with a second external toothing disposed on a single level, which cannot be pivoted satisfactorily on the same axis as that of the planetary gear carrier and the correction star. The tolerances of the guide portions require to be minimized to the greatest possible extent, furthermore, in order to reduce the radial and longitudinal movements, and thus to minimize the risks of butting between the different toothings, in particular those of the planetary gear which is in engagement with internal and external toothings.
Patent Application EP2950164 likewise discloses a device for the display and correction of the phases of the moon. This device implements a specific design of a differential train. The first input is constituted by a wheel in engagement with a 24-hour wheel of a calendar system, on which a spring is mounted. This spring is intended to interact with a correction star that is integral with a wheel of a kinematic correction chain which constitutes the second input of the planetary gear set. The correction star is likewise integral with a pinion that is continuously in engagement with the planetary gears of a planetary gear carrier which constitutes the output of the planetary gear set associated with the element for the display of the moon phase indication. During the conventional operation of the timepiece, the wheel drives the pinion by means of the spring which is in elastic engagement with the correction star. The pinion thus meshes with the planetary gears, which are likewise in engagement with an internal toothing that is integral with the frame of the movement. The meshing of the planetary gears thus induces the rotation of the planetary gear carrier. During the adjustment phase, the actuation of the correction wheel induces the rotation of the star relative to the spring, which is then indexed angularly by the wheel.
A suchlike design is not optimal to the extent that it requires a coupling device between the adjustment mechanism control and the correction wheel, given that the latter rotates continuously. Furthermore, the driving wheel is in direct engagement with the 24-hour wheel of the calendar system, so that it is not possible to correct the calendar independently of the indication of the phases of the moon. Lastly, in order for it to function, the differential train requires a corresponding internal toothing fixed to the frame, which must be in engagement with each of the planetary gears, which is not optimal in terms of the assembly of the device within the timepiece. What is more, the tolerances of the guide portions must be minimized to the greatest possible extent in this case, too, in order to reduce the radial and longitudinal movements, and thus to minimize the risks of butting between the different toothings.
Documents FR2541005, EP2615506 and EP2950164 disclose watch designs in which, in addition to their complexity, a correction of one watch indication is not able to be performed independently of a correction of another watch indication.